1
|
Eco-Evolutionary Dynamics of the Human-Gut Microbiota Symbiosis in a Changing Nutritional Environment. Evol Biol 2022. [DOI: 10.1007/s11692-022-09569-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
AbstractThe operational harmony between living beings and their circumstances, their ever-changing environment, is a constitutive condition of their existence. Nutrition and symbiosis are two essential aspects of this harmony. Disruption of the symbiosis between host and gut microbiota, the so-called dysbiosis, as well as the inadequate diet from which it results, contribute to the etiology of immunometabolic disorders. Research into the development of these diseases is highly influenced by our understanding of the evolutionary roots of metabolic functioning, thereby considering that chronic non-communicable diseases arise from an evolutionary mismatch. However, the lens has been mostly directed toward energy availability and metabolism, but away from our closest environmental factor, the gut microbiota. Thus, this paper proposes a narrative thread that places symbiosis in an evolutionary perspective, expanding the traditional framework of humans’ adaptation to their food environment.
Collapse
|
2
|
Gay L, Dhinaut J, Jullien M, Vitalis R, Navascués M, Ranwez V, Ronfort J. Evolution of flowering time in a selfing annual plant: Roles of adaptation and genetic drift. Ecol Evol 2022; 12:e8555. [PMID: 35127051 PMCID: PMC8794724 DOI: 10.1002/ece3.8555] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 12/10/2021] [Indexed: 11/10/2022] Open
Abstract
Resurrection studies are a useful tool to measure how phenotypic traits have changed in populations through time. If these trait modifications correlate with the environmental changes that occurred during the time period, it suggests that the phenotypic changes could be a response to selection. Selfing, through its reduction of effective size, could challenge the ability of a population to adapt to environmental changes. Here, we used a resurrection study to test for adaptation in a selfing population of Medicago truncatula, by comparing the genetic composition and flowering times across 22 generations. We found evidence for evolution toward earlier flowering times by about two days and a peculiar genetic structure, typical of highly selfing populations, where some multilocus genotypes (MLGs) are persistent through time. We used the change in frequency of the MLGs through time as a multilocus fitness measure and built a selection gradient that suggests evolution toward earlier flowering times. Yet, a simulation model revealed that the observed change in flowering time could be explained by drift alone, provided the effective size of the population is small enough (<150). These analyses suffer from the difficulty to estimate the effective size in a highly selfing population, where effective recombination is severely reduced.
Collapse
Affiliation(s)
- Laurène Gay
- CIRADINRAEInstitut AgroUMR AGAP InstitutUniv MontpellierMontpellierFrance
| | - Julien Dhinaut
- CIRADINRAEInstitut AgroUMR AGAP InstitutUniv MontpellierMontpellierFrance
- Present address:
Evolutionary Biology and Ecology of AlgaeUPMCUniversity of Paris VI, UC, UACH, UMI 3614CNRSSorbonne UniversitésRoscoffFrance
| | - Margaux Jullien
- CIRADINRAEInstitut AgroUMR AGAP InstitutUniv MontpellierMontpellierFrance
- Present address:
INRAUniv. Paris‐SudCNRSAgroParisTechGQE – Le MoulonUniversité Paris‐SaclayGif‐sur‐YvetteFrance
| | - Renaud Vitalis
- CIRADINRAEInstitut AgroIRDCBGPUniv MontpellierMontpellierFrance
| | | | - Vincent Ranwez
- CIRADINRAEInstitut AgroUMR AGAP InstitutUniv MontpellierMontpellierFrance
| | - Joëlle Ronfort
- CIRADINRAEInstitut AgroUMR AGAP InstitutUniv MontpellierMontpellierFrance
| |
Collapse
|
3
|
Levy SB, Leonard WR. The evolutionary significance of human brown adipose tissue: Integrating the timescales of adaptation. Evol Anthropol 2021; 31:75-91. [PMID: 34910348 DOI: 10.1002/evan.21930] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 05/14/2021] [Accepted: 11/19/2021] [Indexed: 12/20/2022]
Abstract
While human adaptability is regarded as a classical topic in anthropology, recent work provides new insight into metabolic adaptations to cold climates and the role of phenotypic plasticity in human evolution. A growing body of literature demonstrates that adults retain brown adipose tissue (BAT) which may play a role in non-shivering thermogenesis. In this narrative review, we apply the timescales of adaptation framework in order to explore the adaptive significance of human BAT. Human variation in BAT is shaped by multiple adaptive modes (i.e., allostasis, acclimatization, developmental adaptation, epigenetic inheritance, and genetic adaptation), and together the adaptive modes act as an integrated system. We hypothesize that plasticity in BAT facilitated the successful expansion of human populations into circumpolar regions, allowing for selection of genetic adaptations to cold climates to take place. Future research rooted in human energetics and biocultural perspectives is essential for understanding BAT's adaptive and health significance.
Collapse
Affiliation(s)
- Stephanie B Levy
- Department of Anthropology, CUNY Hunter College, New York, New York, USA.,New York Consortium in Evolutionary Primatology, New York, New York, USA
| | - William R Leonard
- Department of Anthropology, Northwestern University, Evanston, Illinois, USA
| |
Collapse
|
4
|
Landini A, Yu S, Gnecchi‐Ruscone GA, Abondio P, Ojeda‐Granados C, Sarno S, De Fanti S, Gentilini D, Di Blasio AM, Jin H, Nguyen TT, Romeo G, Prata C, Bortolini E, Luiselli D, Pettener D, Sazzini M. Genomic adaptations to cereal-based diets contribute to mitigate metabolic risk in some human populations of East Asian ancestry. Evol Appl 2021; 14:297-313. [PMID: 33664777 PMCID: PMC7896717 DOI: 10.1111/eva.13090] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 07/20/2020] [Accepted: 08/04/2020] [Indexed: 12/21/2022] Open
Abstract
Adoption of diets based on some cereals, especially on rice, signified an iconic change in nutritional habits for many Asian populations and a relevant challenge for their capability to maintain glucose homeostasis. Indeed, rice shows the highest carbohydrates content and glycemic index among the domesticated cereals and its usual ingestion represents a potential risk factor for developing insulin resistance and related metabolic diseases. Nevertheless, type 2 diabetes and obesity epidemiological patterns differ among Asian populations that rely on rice as a staple food, with higher diabetes prevalence and increased levels of central adiposity observed in people of South Asian ancestry rather than in East Asians. This may be at least partly due to the fact that populations from East Asian regions where wild rice or other cereals such as millet have been already consumed before their cultivation and/or were early domesticated have relied on these nutritional resources for a period long enough to have possibly evolved biological adaptations that counteract their detrimental side effects. To test such a hypothesis, we compared adaptive evolution of these populations with that of control groups from regions where the adoption of cereal-based diets occurred many thousand years later and which were identified from a genome-wide dataset including 2,379 individuals from 124 East Asian and South Asian populations. This revealed selective sweeps and polygenic adaptive mechanisms affecting functional pathways involved in fatty acids metabolism, cholesterol/triglycerides biosynthesis from carbohydrates, regulation of glucose homeostasis, and production of retinoic acid in Chinese Han and Tujia ethnic groups, as well as in people of Korean and Japanese ancestry. Accordingly, long-standing rice- and/or millet-based diets have possibly contributed to trigger the evolution of such biological adaptations, which might represent one of the factors that play a role in mitigating the metabolic risk of these East Asian populations.
Collapse
Affiliation(s)
- Arianna Landini
- Laboratory of Molecular Anthropology & Centre for Genome BiologyDepartment of Biological, Geological and Environmental SciencesUniversity of BolognaBolognaItaly
- Centre for Global Health ResearchUsher Institute of Population Health Sciences and InformaticsUniversity of EdinburghEdinburghUK
| | - Shaobo Yu
- Laboratory of Molecular Anthropology & Centre for Genome BiologyDepartment of Biological, Geological and Environmental SciencesUniversity of BolognaBolognaItaly
| | | | - Paolo Abondio
- Laboratory of Molecular Anthropology & Centre for Genome BiologyDepartment of Biological, Geological and Environmental SciencesUniversity of BolognaBolognaItaly
| | - Claudia Ojeda‐Granados
- Laboratory of Molecular Anthropology & Centre for Genome BiologyDepartment of Biological, Geological and Environmental SciencesUniversity of BolognaBolognaItaly
- Department of Molecular Biology in MedicineCivil Hospital of Guadalajara “Fray Antonio Alcalde” and Health Sciences CenterUniversity of GuadalajaraGuadalajaraMexico
| | - Stefania Sarno
- Laboratory of Molecular Anthropology & Centre for Genome BiologyDepartment of Biological, Geological and Environmental SciencesUniversity of BolognaBolognaItaly
| | - Sara De Fanti
- Interdepartmental Centre Alma Mater Research Institute on Global Challenges and Climate ChangeUniversity of BolognaBolognaItaly
| | - Davide Gentilini
- Department of Brain and Behavioral SciencesUniversity of PaviaPaviaItaly
- Italian Auxologic Institute IRCCSCusano Milanino, MilanItaly
| | | | - Hanjun Jin
- Department of Biological SciencesCollege of Natural ScienceDankook UniversityCheonanSouth Korea
| | | | - Giovanni Romeo
- Medical Genetics UnitS. Orsola HospitalUniversity of BolognaBolognaItaly
- European School of Genetic MedicineItaly
| | - Cecilia Prata
- Department of Pharmacy and BiotechnologyUniversity of BolognaBolognaItaly
| | | | - Donata Luiselli
- Department of Cultural HeritageUniversity of BolognaRavennaItaly
| | - Davide Pettener
- Laboratory of Molecular Anthropology & Centre for Genome BiologyDepartment of Biological, Geological and Environmental SciencesUniversity of BolognaBolognaItaly
| | - Marco Sazzini
- Laboratory of Molecular Anthropology & Centre for Genome BiologyDepartment of Biological, Geological and Environmental SciencesUniversity of BolognaBolognaItaly
- Interdepartmental Centre Alma Mater Research Institute on Global Challenges and Climate ChangeUniversity of BolognaBolognaItaly
| |
Collapse
|
5
|
Tompkins CL, Laurent J, Brock DW. Food Addiction: A Barrier for Effective Weight Management for Obese Adolescents. Child Obes 2017; 13:462-469. [PMID: 28727935 DOI: 10.1089/chi.2017.0003] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BACKGROUND Findings from studies of food addiction in adults suggest those with food addiction are less successful in weight-loss interventions. Little is known about food addiction in obesity treatment-seeking adolescents; therefore, the purpose of this study was to explore the prevalence of food addiction and correlates of food addiction symptoms in obese adolescents entering an outpatient, weight management program. METHODS Obese adolescents (n = 26) were administered the Yale Food Addiction Scale for Children (YFAS-C), measures of appetitive responsiveness, and health-related quality of life (HRQOL) before and following a 12-week, outpatient, behavioral weight management program. Descriptive statistics and correlations between YFAS-C symptoms and study variables were performed and further examined with linear regression. Baseline differences were compared between those meeting criteria for food addiction to those who did not (independent t-tests) and pre-postweight management program changes were examined (paired t-tests). RESULTS 30.7% met criteria for food addiction and 50% reported ≥3 symptoms. Number of YFAS-C symptoms was correlated with appetitive responsiveness (r = 0.57, p < 0.05) and inversely correlated with all domains of HRQOL (r = 0.47-0.53, p < 0.05). Attrition rate was higher in adolescents with food addiction compared to those without (62.5% vs. 44.4%, p < 0.05). CONCLUSIONS Adolescents with food addiction or with a higher number of food addiction symptoms may warrant additional resources to support adherence to and retention with a weight management program. Implementing screening measures for food addiction before enrolling in a weight management program may be an effective strategy to identify adolescents who may benefit from adjunct modalities.
Collapse
Affiliation(s)
- Connie L Tompkins
- 1 Department of Rehabilitation and Movement Science, University of Vermont , Burlington, VT
| | | | - David W Brock
- 1 Department of Rehabilitation and Movement Science, University of Vermont , Burlington, VT
| |
Collapse
|
6
|
Huang S, Zhang L, Rehman MU, Iqbal MK, Lan Y, Mehmood K, Zhang H, Qiu G, Nabi F, Yao W, Wang M, Li J. High altitude hypoxia as a factor that promotes tibial growth plate development in broiler chickens. PLoS One 2017; 12:e0173698. [PMID: 28282429 PMCID: PMC5345845 DOI: 10.1371/journal.pone.0173698] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Accepted: 02/25/2017] [Indexed: 01/21/2023] Open
Abstract
Tibial dyschondroplasia (TD) is one of the most common problems in the poultry industry and leads to lameness by affecting the proximal growth plate of the tibia. However, due to the unique environmental and geographical conditions of Tibet, no case of TD has been reported in Tibetan chickens (TBCs). The present study was designed to investigate the effect of high altitude hypoxia on blood parameters and tibial growth plate development in chickens using the complete blood count, morphology, and histological examination. The results of this study showed an undesirable impact on the overall performance, body weight, and mortality of Arbor Acres chickens (AACs) exposed to a high altitude hypoxic environment. However, AACs raised under hypoxic conditions showed an elevated number of red blood cells (RBCs) and an increase in hemoglobin and hematocrit values on day 14 compared to the hypobaric normoxia group. Notably, the morphology and histology analyses showed that the size of tibial growth plates in AACs was enlarged and that the blood vessel density was also higher after exposure to the hypoxic environment for 14 days, while no such change was observed in TBCs. Altogether, our results revealed that the hypoxic environment has a potentially new role in increasing the blood vessel density of proximal tibial growth plates to strengthen and enhance the size of the growth plates, which may provide new insights for the therapeutic manipulation of hypoxia in poultry TD.
Collapse
Affiliation(s)
- Shucheng Huang
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Lihong Zhang
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Mujeeb Ur Rehman
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Muhammad Kashif Iqbal
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Yanfang Lan
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Khalid Mehmood
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Hui Zhang
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Gang Qiu
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, People's Republic of China
- Laboratory of Detection and Monitoring of Highland Animal Disease, Tibet Agriculture and Animal Husbandry College, Linzhi Tibet, People's Republic of China
| | - Fazul Nabi
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, People's Republic of China
- Faculty of Veterinary & Animal Sciences, Lasbela University of Agriculture, Water and Marine Sciences Uthal, Balochistan, Pakistan
| | - Wangyuan Yao
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Meng Wang
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Jiakui Li
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, People's Republic of China
- Laboratory of Detection and Monitoring of Highland Animal Disease, Tibet Agriculture and Animal Husbandry College, Linzhi Tibet, People's Republic of China
- * E-mail:
| |
Collapse
|
7
|
Jia C, He L, Li P, Liu H, Wei Z. Effect of egg composition and oxidoreductase on adaptation of Tibetan chicken to high altitude. Poult Sci 2016; 95:1660-1665. [DOI: 10.3382/ps/pew048] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 01/03/2016] [Indexed: 12/17/2022] Open
|
8
|
Wells JCK. Commentary: The thrifty phenotype and the hierarchical preservation of tissues under stress. Int J Epidemiol 2016; 42:1223-7. [PMID: 24159066 DOI: 10.1093/ije/dyt130] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
|
9
|
Ng J, Trask JS, Smith DG, Kanthaswamy S. Heterospecific SNP diversity in humans and rhesus macaque (Macaca mulatta). J Med Primatol 2015; 44:194-201. [PMID: 25963897 DOI: 10.1111/jmp.12174] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/09/2015] [Indexed: 11/30/2022]
Abstract
BACKGROUND Conservation of single nucleotide polymorphisms (SNPs) between human and other primates (i.e., heterospecific SNPs) in candidate genes can be used to assess the utility of those organisms as models for human biomedical research. METHODS A total of 59,691 heterospecific SNPs in 22 rhesus macaques and 20 humans were analyzed for human trait associations and 4207 heterospecific SNPs biallelic in both taxa were compared for genetic variation. RESULTS Variation comparisons at the 4207 SNPs showed that humans were more genetically diverse than rhesus macaques with observed and expected heterozygosities of 0.337 and 0.323 vs. 0.119 and 0.102, and minor allele frequencies of 0.239 and 0.063, respectively. In total, 431 of the 59,691 heterospecific SNPs are reportedly associated with human-specific traits. CONCLUSION While comparisons between human and rhesus macaque genomes are plausible, functional studies of heterospecific SNPs are necessary to determine whether rhesus macaque alleles are associated with the same phenotypes as their corresponding human alleles.
Collapse
Affiliation(s)
- Jillian Ng
- Molecular Anthropology Laboratory, Department of Anthropology, University of California, Davis, CA, USA
| | - Jessica Satkoski Trask
- Molecular Anthropology Laboratory, Department of Anthropology, University of California, Davis, CA, USA.,California National Primate Research Center, University of California, Davis, CA, USA
| | - David Glenn Smith
- Molecular Anthropology Laboratory, Department of Anthropology, University of California, Davis, CA, USA.,California National Primate Research Center, University of California, Davis, CA, USA
| | - Sree Kanthaswamy
- Molecular Anthropology Laboratory, Department of Anthropology, University of California, Davis, CA, USA.,California National Primate Research Center, University of California, Davis, CA, USA.,School of Mathematics and Natural Sciences, Arizona State University (ASU) at the West Campus, Glendale, AZ, USA.,Department of Environmental Toxicology, University of California, Davis, CA, USA
| |
Collapse
|
10
|
Wang SP, Yang H, Wu JW, Gauthier N, Fukao T, Mitchell GA. Metabolism as a tool for understanding human brain evolution: lipid energy metabolism as an example. J Hum Evol 2014; 77:41-9. [PMID: 25488255 DOI: 10.1016/j.jhevol.2014.06.013] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 03/24/2014] [Accepted: 06/18/2014] [Indexed: 10/24/2022]
Abstract
Genes and the environment both influence the metabolic processes that determine fitness. To illustrate the importance of metabolism for human brain evolution and health, we use the example of lipid energy metabolism, i.e. the use of fat (lipid) to produce energy and the advantages that this metabolic pathway provides for the brain during environmental energy shortage. We briefly describe some features of metabolism in ancestral organisms, which provided a molecular toolkit for later development. In modern humans, lipid energy metabolism is a regulated multi-organ pathway that links triglycerides in fat tissue to the mitochondria of many tissues including the brain. Three important control points are each suppressed by insulin. (1) Lipid reserves in adipose tissue are released by lipolysis during fasting and stress, producing fatty acids (FAs) which circulate in the blood and are taken up by cells. (2) FA oxidation. Mitochondrial entry is controlled by carnitine palmitoyl transferase 1 (CPT1). Inside the mitochondria, FAs undergo beta oxidation and energy production in the Krebs cycle and respiratory chain. (3) In liver mitochondria, the 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) pathway produces ketone bodies for the brain and other organs. Unlike most tissues, the brain does not capture and metabolize circulating FAs for energy production. However, the brain can use ketone bodies for energy. We discuss two examples of genetic metabolic traits that may be advantageous under most conditions but deleterious in others. (1) A CPT1A variant prevalent in Inuit people may allow increased FA oxidation under nonfasting conditions but also predispose to hypoglycemic episodes. (2) The thrifty genotype theory, which holds that energy expenditure is efficient so as to maximize energy stores, predicts that these adaptations may enhance survival in periods of famine but predispose to obesity in modern dietary environments.
Collapse
Affiliation(s)
- Shu Pei Wang
- Division of Medical Genetics, Department of Pediatrics, Université de Montréal and CHU Sainte-Justine, 3175 Côte Sainte-Catherine, Montreal H3T 1C5, QC, Canada
| | - Hao Yang
- Division of Medical Genetics, Department of Pediatrics, Université de Montréal and CHU Sainte-Justine, 3175 Côte Sainte-Catherine, Montreal H3T 1C5, QC, Canada; Laboratory of Animal Fat Deposition and Muscle Development, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Jiang Wei Wu
- Division of Medical Genetics, Department of Pediatrics, Université de Montréal and CHU Sainte-Justine, 3175 Côte Sainte-Catherine, Montreal H3T 1C5, QC, Canada
| | - Nicolas Gauthier
- Division of Medical Genetics, Department of Pediatrics, Université de Montréal and CHU Sainte-Justine, 3175 Côte Sainte-Catherine, Montreal H3T 1C5, QC, Canada
| | - Toshiyuki Fukao
- Department of Pediatrics, Gifu University School of Medicine, Gifu 500, Japan
| | - Grant A Mitchell
- Division of Medical Genetics, Department of Pediatrics, Université de Montréal and CHU Sainte-Justine, 3175 Côte Sainte-Catherine, Montreal H3T 1C5, QC, Canada.
| |
Collapse
|
11
|
Genomic analysis of natural selection and phenotypic variation in high-altitude mongolians. PLoS Genet 2013; 9:e1003634. [PMID: 23874230 PMCID: PMC3715426 DOI: 10.1371/journal.pgen.1003634] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Accepted: 05/31/2013] [Indexed: 01/01/2023] Open
Abstract
Deedu (DU) Mongolians, who migrated from the Mongolian steppes to the Qinghai-Tibetan Plateau approximately 500 years ago, are challenged by environmental conditions similar to native Tibetan highlanders. Identification of adaptive genetic factors in this population could provide insight into coordinated physiological responses to this environment. Here we examine genomic and phenotypic variation in this unique population and present the first complete analysis of a Mongolian whole-genome sequence. High-density SNP array data demonstrate that DU Mongolians share genetic ancestry with other Mongolian as well as Tibetan populations, specifically in genomic regions related with adaptation to high altitude. Several selection candidate genes identified in DU Mongolians are shared with other Asian groups (e.g., EDAR), neighboring Tibetan populations (including high-altitude candidates EPAS1, PKLR, and CYP2E1), as well as genes previously hypothesized to be associated with metabolic adaptation (e.g., PPARG). Hemoglobin concentration, a trait associated with high-altitude adaptation in Tibetans, is at an intermediate level in DU Mongolians compared to Tibetans and Han Chinese at comparable altitude. Whole-genome sequence from a DU Mongolian (Tianjiao1) shows that about 2% of the genomic variants, including more than 300 protein-coding changes, are specific to this individual. Our analyses of DU Mongolians and the first Mongolian genome provide valuable insight into genetic adaptation to extreme environments. Throughout history, Mongolians have survived the harsh conditions of northern latitudes, including seasonal cold, drought, and a restricted diet. Approximately 500 years ago, nomadic Deedu (DU; “at high altitude”) Mongolians migrated from the Mongolian steppes to the northeastern highlands of the Qinghai-Tibetan Plateau. Using high-density SNP data, we demonstrate that present-day DU Mongolians share genetic ancestry with other Mongolians and with Tibetans. High-altitude selection candidate genes previously identified in the latter population (EPAS1, PKLR, CYP2E1), and PPARG, a gene long hypothesized to play a role in metabolic adaptation, are among the strongest adaptive signals in DU Mongolians. Furthermore, we show that hemoglobin concentration, associated with high-altitude adaptation in Tibetans, is intermediate in DU Mongolians compared to Tibetans and Han Chinese at comparable altitudes. Whole-genome sequence from a DU Mongolian shows that approximately 300 protein-coding changes are specific to this individual. Our analyses provide new perspectives on genetic variation and adaptation to extreme environments.
Collapse
|
12
|
Davis C. From passive overeating to "food addiction": a spectrum of compulsion and severity. ISRN OBESITY 2013; 2013:435027. [PMID: 24555143 PMCID: PMC3901973 DOI: 10.1155/2013/435027] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 04/16/2013] [Indexed: 01/17/2023]
Abstract
A psychobiological dimension of eating behaviour is proposed, which is anchored at the low end by energy intake that is relatively well matched to energy output and is reflected by a stable body mass index (BMI) in the healthy range. Further along the continuum are increasing degrees of overeating (and BMI) characterized by more severe and more compulsive ingestive behaviours. In light of the many similarities between chronic binge eating and drug abuse, several authorities have adopted the perspective that an apparent dependence on highly palatable food-accompanied by emotional and social distress-can be best conceptualized as an addiction disorder. Therefore, this review also considers the overlapping symptoms and characteristics of binge eating disorder (BED) and models of food addiction, both in preclinical animal studies and in human research. It also presents this work in the context of the modern and "toxic" food environment and therein the ubiquitous triggers for over-consumption. We complete the review by providing evidence that what we have come to call "food addiction" may simply be a more acute and pathologically dense form of BED.
Collapse
Affiliation(s)
- Caroline Davis
- Kinesiology & Health Sciences, Faculty of Health, York University, 343 Bethune College, 4700 Keele Street, Toronto, ON, Canada M3J 1P3
| |
Collapse
|
13
|
Ségurel L, Austerlitz F, Toupance B, Gautier M, Kelley JL, Pasquet P, Lonjou C, Georges M, Voisin S, Cruaud C, Couloux A, Hegay T, Aldashev A, Vitalis R, Heyer E. Positive selection of protective variants for type 2 diabetes from the Neolithic onward: a case study in Central Asia. Eur J Hum Genet 2013; 21:1146-51. [PMID: 23340510 DOI: 10.1038/ejhg.2012.295] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 10/30/2012] [Accepted: 12/11/2012] [Indexed: 11/09/2022] Open
Abstract
The high prevalence of type 2 diabetes and its uneven distribution among human populations is both a major public health concern and a puzzle in evolutionary biology. Why is this deleterious disease so common, while the associated genetic variants should be removed by natural selection? The 'thrifty genotype' hypothesis proposed that the causal genetic variants were advantageous and selected for during the majority of human evolution. It remains, however, unclear whether genetic data support this scenario. In this study, we characterized patterns of selection at 10 variants associated with type 2 diabetes, contrasting one herder and one farmer population from Central Asia. We aimed at identifying which alleles (risk or protective) are under selection, dating the timing of selective events, and investigating the effect of lifestyle on selective patterns. We did not find any evidence of selection on risk variants, as predicted by the thrifty genotype hypothesis. Instead, we identified clear signatures of selection on protective variants, in both populations, dating from the beginning of the Neolithic, which suggests that this major transition was accompanied by a selective advantage for non-thrifty variants. Combining our results with worldwide data further suggests that East Asia was particularly prone to such recent selection of protective haplotypes. As much effort has been devoted so far to searching for thrifty variants, we argue that more attention should be paid to the evolution of non-thrifty variants.
Collapse
Affiliation(s)
- Laure Ségurel
- 1] Eco-Anthropologie et Ethnobiologie, UMR 7206, Muséum National d'Histoire Naturelle - Centre National de la Recherche Scientifique - Université Paris 7 Diderot, Paris, France [2] Department of Human Genetics, University of Chicago, Chicago, IL, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|